As Apple was completely and utterly useless in this instance (they will only support ARD working on local networks ... like that's useful) ... I'm hoping one of the brains here might have some suggestions ... ideas.
Let's start with my current ARD setup has been working fine for many, many years. Primarily, I use it to log into client computers across the city to check up on things and check out the server, etc. All of the client computers are set with a fixed IP address. All of the proper mappings have been created on the router (mapping the public IP address with the ARD ports to each individual IP address in the office). All has been great ... until recently. This client decided that he wanted an install of ARD on his computer so that he could log into computers at his office when he was away. He purchased from the app store and I walked him through going to Add by Address in the file many, typing in the public IP address, authentication credentials, and the remote management and screen sharing ports. The computer was added to the list and its current status was displayed. But, within a couple of seconds, the listed IP address changed from the public IP address required for remote access to the internal computer IP address ... rendering the computer unreachable.
Thinking this was a bit odd, I looked at my perfectly functioning ARD, brought up and controlled the computer that he was trying to add and decided to delete it from my list of All Computers and add it back in. So, of course, exactly the same thing happened and now I cannot add back in and control a computer that I had been controlling 30 seconds ago. Apple, in their infinite wisdom, has decided that it is a network issue (completely disregarding the fact that I showed them a working computer that I deleted and then couldn't add back in).
So, does anyone have any idea whatsoever? If so, thanks. If not, thanks for reading through this missive anyway
Remote Desktop, OS X El Capitan (10.11.6)
